What is the definition of altruism, its conditions, and its nullifiers?

Altruism is: prioritizing others over oneself and one's worldly gains, out of desire for religious gains. It stems from strong certainty, confirmed love, and patience. Altruism is preferring others with something even when one needs it oneself. Its opposite is selfishness. Altruism's antithesis is stinginess. The conditions and nullifiers become clear through these definitions.